The basic structure of flat-panel solar collectors
Flat-panel solar collectors mainly by the heat-absorbing panels, transparent cover, insulation materials and shell parts.
When the flat panel collector is working, the solar radiation passes through the transparent cover plate, projects on the heat absorption plate, is absorbed by the heat absorption plate and is converted into heat energy, and then transfers the heat to the heat transmission medium in the heat absorption plate, At the same time, the heat-absorbing plate after the temperature increase inevitably dissipates heat to the surroundings through conduction, convection and radiation and becomes the heat of the heat collector loss.
(1) heat-absorbing plate
Heat-absorbing plate is a flat-panel solar collector to absorb solar radiation and heat transfer to the heat transfer medium components. In plate-shaped heat-absorbing panels, there are usually arranged pipes and headers. Row pipe refers to the longitudinal arrangement of the heat absorption plate and constitute the components of the fluid passage; header refers to the upper end and the lower end of the heat absorption plate to connect a number of rows of pipes and constitute the fluid passage components.
Heat absorption plate material of many different types, copper, aluminum, copper and aluminum composite, stainless steel, galvanized steel, plastic, rubber and so on.
(2) transparent cover
Transparent cover plate is a flat plate solar collector plate heat absorption plate and by the transparent (or translucent) plate material composed of the material. It has three main functions. First, through the sun radiation, so that it is projected on the heat-absorbing plate; the second is to protect the heat-absorbing plate, so that it is not eroded by dust and rain and snow; the third is the formation of the greenhouse effect to prevent the heat-absorbing plate after the temperature increases through Convection and radiation to the surrounding environment.
There are two main types of materials used for the transparent cover: flat glass and glass.
(3) insulation layer
Insulation layer is a flat panel solar collector to inhibit the heat absorption plate through the conduction to the surrounding environment of the heat dissipation components.
Materials used for the insulation layer are: rock wool, mineral wool, polyurethane, polystyrene and so on. Insulation material thermal conductivity should not exceed 0.055W / (m. K), so that the above-mentioned materials can meet the requirements. Rock wool is currently used more.
Shell is a flat panel solar collector protection and fixed heat-absorbing plate, transparent cover and insulation components.
The materials used for the shell are: aluminum alloy plate, stainless steel plate, carbon steel plate, plastic, glass steel and so on. In order to improve the sealing of the shell, the company's products have been used aluminum plate molding process.